Question: If $a + b = -7$ and $x + y = 10$, what is $-4b - 4a + 7y + 7x$ ?
Explanation: $= -4a - 4b + 7x + 7y$ $= (-4) \cdot (a + b) + (7) \cdot (x + y)$ $= (-4) \cdot (-7) + (7) \cdot (10)$ $= 28 + 70$ $= 98$